Metal organic framework-assisted copper-modified titania (Cu/TiO2) with abundant exposed active sites and highly accessible pore channels for an enhanced photo-generation of hydrogen

Metal-doping is a common strategy for establishing active sites on photocatalyst, but appropriately exposing them for maximized atomic utilization remains a great challenge in photocatalytic research. Herein, we propose a metal organic framework (MOF)-assisted approach to synthesis copper-modified titania (Cu-TiO 2 /Cu) photocatalyst with homogenously distributed and highly accessible active sites in its matrix. Significantly, an MOF precursor, namely NH 2 -MIL-125, with co-chelation of titania (Ti) and copper (Cu) was subjected to mild calcination, subsequently results in Cu-modified TiO 2 with highly accessible channels to its inner surface. These channels provide not only a large reactive surface (>400 m 2 g -1 ); they also enable facile modifying route for the pre-deposited Cu in prior to photoreaction. Specifically, NH 3 treatment was applied to partially reduce deposited Cu ions (Cu + and Cu 2+ ) into Cu nanoparticles, where their interplays realize improved optical properties and charge separation during photoreactions. Furthermore, the NH 3 -induced Cu nanoparticles could also serve as the adsorptive site for H + , thereby enabling 5629 μmol h -1 g -1 H 2 generation over the optimum photocatalyst of Cu 20 /TiO 2 /Cu 500 . Such performance is associated to 35.44 and 1.71-fold improvements compared to pure TiO 2 (Cu 0 /TiO 2 ) and untreated Cu-ion modified TiO 2 (Cu 20 /TiO 2 ), respectively. This work offers a new synthetic strategy for obtaining photocatalyst with evenly distributed and highly accessible active sites, thus improving the commensurability of photocatalytic H 2 generation from the industrial perspective.